Throttle control



March 7, 1944.

M. UDA

THROTTLE CO Filed July 13, 1942 NWO Patented Mar. 7, 1944- THROTTLECONTROL Stanley M. Udale, Detroit, Mich., assignor to George M. Holleyand Earl Holley Application July 13, 1942, Serial No. 450,825

2 Claims.

The object of my invention is to open and close the throttle of anairplane engine carburetor by remote control, that is to say, toeliminate all the links that are now in use and substitute two pipes,one connected to the supercharger and delivering air under superchargerpressure to the dash, and the other pipe conveying air undersupercharger pressure back to the throttle control mounted on the airentrance. With this arrangement, the pilot merely admits more or less ofthe supercharger pressure to the control and opens the throttle more orless without any links connecting the cockpit with the engine.

The drawing shows diagrammatically a preferred form of my invention.

In the drawing, I is the air entrance in which is shown a nozzle l3discharging therein. However, it has been usual in recent years to placethis nozzle IE on the engine side of the throttle. l is this throttleand I2 is the throttle lever. I3 is the rod controlling the throttle.The rod i3 is pushed to the right by the spring 4 which closes thethrottle. The rod 13 is pushed to the left by the spring l5. The springI5 is located in the chamber 35 connected with the pipe I! with the airentrance l8 located on the engine side of the throttle II. The spring I4is located in the chamber l9 connected with the pipe 20 with the chamber2|, which can communicate with the atmosphere, when the spring loadedvalve 22 is opened by atmospheric pressure.

The chamber 2| also communicates with a chamber 23 past a gravitynon-return check valve 24. The chamber 23 communicates through a pipe 32with the supercharger 25. The chamber 23 is thus maintained at thepressure of the supercharger.

The valve 26 controls the opening between the chamber 2| and the pipe20. The valve 26 is connected to an evacuated bellows 2! inside of whichthere is a compression spring 28.

The rack 29 is connected with the bellows 2i and is controlled by apinion 30 which is rotated by the manually controlled lever 3|. Whenthis control lever moves to the left clockwise, the rack 29 moves to theright, the valve 26 moves to the right, and the supercharger pressure isadmitted through the pipe 32 to the chamber 23 past the check valve 24,into the chamber 2|, past the valve 26, through the pipe 20, into thechamber l3. Supercharger pressure is then exerted against a diaphragm 33which separates the two chambers 35 and IS). The diaphragm 33 isconnected to the rod l3, and assuming that the throttle is open, thethrottle |l closes under the influence of the supercharger pressureuntil the supercharger pressure 25 falls to a point at which the valve26 is permitted to close, so as to restrict the flow of compressed airinto the chamberl9 and to bring the throttle to a stationary position.By this means the supercharger pressure 25 is maintained at the pressureselected by the lever 3|. When the supercharger pressure falls below theatmosphere, atmospheric pressure is admitted past the Valve 22, so thatthe servornotor |4|533|9--35 thereupon operates with atmosphericpressure instead of with supercharger pressure.

A restricted by-pass 34 connects the two chambers 35 and I9 together forobvious reasons. It would be noted that pipe 1 has two branches. Thisdouble connection of pipe ll with chamber 35 reduces the ever presenthazard of freezing. If the lower of the two pipes should freeze, theupper would remain open and the device would remain in an operativecondition for a longer period of time before it completely froze up. Itis therefore, a device to reduce as much as possible the ever presenthazard of freezing.

What I claim is:

1. A throttle control for an airplane engine having an air passageleading to said engine, a throttle valve therein, a throttle levertherefore, a supercharger communicating with said air passage, achamber, a passage connecting said chamber with the engine side of saidthrottle, a movable wall in said. chamber, a second chamber located onopposite side of movable wall, a passage connecting said second chamberwith said supercharger, a valve in said passage, a third chamber in freecommunication with said supercharger pressure, an evacuated element insaid third chamber, spring means for supporting said evacuated chamberagainst the effect of said supercharger pressure, manually operatedmeans engaging with one end of said evacuated chamber, the other endbeing connected to said valve, said valve being adapted to be opened byan increase in supercharger pressure and to be closed by an increase inpressure applied by said manually operated means, the opening of saidvalve being adapted to close said throttle.

2. A throttle control for an internal combustion engine having an airpassage leading to said engine, a throttle valve therein, a throttlelever therefor, spring means adapted to open said throttle, superchargercommunicating with said air passage, a chamber in free communicationwith said supercharger pressure, an evacuated element in said chambersecond spring means for supporting said evacuated element against theeffect of said supercharger pressure, manually operated means engagingwith one of said evacuated element and said supporting spring, fluidpressure means adapted to close said throttle, a valve controlling theflow of said fluid pressure means, said valve being connected to theother end of said evacuated chamber whereby when said second spring iscompressed by the efiect of said supercharger pressure on said evacuatedelement, said valve is opened and said throttle is closed by said fluidpressure and when said evacuated element and its supporting spring iscompressed by said manually operated means, said valve is closed andsaid throttle is opened by said first mentioned spring.

STANLEY M. UDALE.

